Dietary Sources of Inulin
Inulin is primarily obtained from chicory root, Jerusalem artichoke, onions, and cereal grains, with chicory root being the predominant industrial source for extraction. 1
Primary Natural Sources
The richest dietary sources of inulin include:
- Chicory root (Cichorium intybus): The primary industrial source for inulin extraction and production 2
- Jerusalem artichoke tubers: One of the most concentrated natural sources, commonly used as raw material for commercial inulin production 3
- Onions: Contain naturally occurring inulin as a storage carbohydrate 1, 4
- Cereal grains: Contain 2-3% inulin by weight 1
Secondary Vegetable and Plant Sources
Additional vegetables and plants containing inulin include:
- Garlic: Contains inulin as part of its fructan content 3, 5
- Leeks: Natural dietary source of inulin 5
- Wheat: Contains inulin among other fructan compounds 5
- Barley: Recognized source of inulin 3
- Artichokes: Contain naturally occurring inulin 5
- Dahlia: Another plant source, though less commonly used for extraction 3
Chemical Structure and Classification
Inulin is classified as a β-1-2 fructan with a linear structure of fructose residues, with or without a terminal α-D-glucosyl unit 1. The degree of polymerization ranges from 2 to 60 units 6. It functions as a storage carbohydrate in over 36,000 plant species 3.
Industrial and Functional Food Applications
- Commercial extraction: Chicory root and Jerusalem artichoke are the preferred industrial sources due to their high inulin concentration 3, 2
- Food fortification: Inulin is added to baked goods, beverages, dairy products, breakfast cereals, and granola bars as a dietary fiber supplement 1
- Prebiotic classification: Inulin is definitively classified as a prebiotic dietary fiber, not a probiotic or fermented food 6
Practical Considerations
When seeking dietary inulin, focus on whole vegetables rather than processed sources. Chicory root and Jerusalem artichoke provide the highest concentrations, while onions, garlic, and leeks offer moderate amounts that can be easily incorporated into daily meals 1, 3. Industrial inulin supplements are extracted primarily from chicory root and are widely available as functional food ingredients 2.